Multivariable output feedback robust adaptive tracking control design for a class of delayed systems

Abstract

In this paper, we develop a model reference adaptive control scheme for a class of multi-input multi-output nonlinearly perturbed dynamic systems with unknown time-varying state delays which is also robust with respect to an external disturbance with unknown bounds. The output feedback adaptive control scheme uses feedback actions only, and thus does not require a direct measurement of the command or disturbance signals. A suitable Lyapunov–Krasovskii type functional is introduced to design the adaptation algorithms and to prove stability.